1. Field of the Invention
The invention pertains to a paint spray pistol.
2. Discussion of the Related Art
When working with a spray pistol it is desirable to adjust the spray pressure so that an optimum atomizing is achieved to ensure an optimum painting result at a good working speed and at a high application efficiency. If the spray pressure is too low, for examples changes in color tone in the base lacquer, or an increase in the orange hue in a clear lacquer and unilacquer, or a reduction in the working speed and possibly the formation of streaks may occur. On the other hand, if the spray pressure is too great, the result may be large mists of the sprayed material and thus greater losses and undesirable pollution of the working environment. During the spray process as well, the available pressure should be monitored in order to detect, for example, any potential pressure drop through additional power consumers in the compressed air supply network, or a pressure increase through connection of resources.
For adjusting and monitoring of the peak pressure, a pressure control valve with pressure gauge is often inlet-connected to the spray pistol. The pressure is adjustable by means of an adjusting knob on the pressure control valve and can be read off at the pressure gauge. However, this pressure control valve located at the air inlet to the paint spray pistol results in lengthening of the spray pistol, so that its handling features are not as good. In addition, the pressure gauge or the pressure control valve causes a pressure drop due to internal bypasses. In addition, as a rule the screwed on pressure control valve has to be dismantled in washing devices or cleaning tubs for cleaning of the spray pistol, since the indicating accuracy of the pressure gauge can be adversely affected by any penetrated solvent or lacquer or paint residues. The pressure control valve with the pressure gauge must therefore be unscrewed for each cleaning process, which is associated with considerable labor expense.
Paint spray pistols are already known that have a connection on the underside of the handle for connecting a conventional pressure gauge. The pressure gauges normally used have a semi-circular or helical-curved steel tube spring as pressure sensor, as a rule, whose pressure-based change in shape is displayed by a pointer on a corresponding dial. The steel tube spring and the display device are located in a separate housing. But with this design as well, the handling of the spray pistol is adversely affected by the connected pressure gauge. In addition, the pressure gauges have to be detachable for cleaning, so that relatively complicated coupling or connecting systems are needed for connection of the pressure gauge to the spray pistols.
It has already been proposed to attach a conventional pressure gauge to one side of the pistol body. These spray pistols as well have poor handling properties due to the pressure gauge protruding to the side. In addition, a spray pistol of this kind has to be handled with exceptional care so that the lateral protruding pressure gauge will not be damaged when the spray pistol is set down.
The purpose of the invention is to create a compact and handy spray pistol with a pressure measuring device which is simple to monitor during the spray process.